Quarterly report pursuant to Section 13 or 15(d)

SENIOR AND CONVERTIBLE SENIOR NOTES, NET - Schedule of Senior and Convertible Senior Notes, Net (Details)

v3.8.0.1
SENIOR AND CONVERTIBLE SENIOR NOTES, NET - Schedule of Senior and Convertible Senior Notes, Net (Details) - Senior Notes [Member] - USD ($)
$ in Thousands
Sep. 30, 2017
Jun. 06, 2017
Dec. 31, 2016
Debt Instrument [Line Items]      
Net debt issuance costs $ (10,262)   $ (8,230)
Senior and convertible senior notes, net 1,266,160   1,095,119
4.50% senior notes due 2018 [Member]      
Debt Instrument [Line Items]      
Senior and convertible senior notes, gross $ 175,000   $ 175,000
Stated interest rate 4.50%   4.50%
7.15% senior notes due 2020 [Member]      
Debt Instrument [Line Items]      
Senior and convertible senior notes, gross $ 301,422   $ 301,849
Stated interest rate 7.15%   7.15%
Unamortized premium $ 1,422   $ 1,849
7.00% senior notes due 2022 [Member]      
Debt Instrument [Line Items]      
Senior and convertible senior notes, gross $ 300,000   $ 300,000
Stated interest rate 7.00%   7.00%
6.00% senior notes due 2025 [Member]      
Debt Instrument [Line Items]      
Senior and convertible senior notes, gross $ 200,000   $ 200,000
Stated interest rate 6.00%   6.00%
5.125% senior notes due 2027 [Member]      
Debt Instrument [Line Items]      
Senior and convertible senior notes, gross $ 300,000   $ 0
Stated interest rate 5.125% 5.125%  
1.875% convertible senior notes due 2032 [Member]      
Debt Instrument [Line Items]      
Senior and convertible senior notes, gross $ 0   $ 126,500
Stated interest rate 1.875%   1.875%